In this paper we propose two types of time-of-day traffic assignment models which can describe real traffic flows by hour of the day over a network. Both of the models require some modification of demand flows among the adjacent hours for the conservation law of flows. In the first model, which we call link-flow modification method, the modification is done based on link flows, and in the second model, which we call OD-flow modification method, the modification is done based on OD flows. It is shown that the latter method can be formulated as the Beckmann-type user equilibrium assignment problem. Two models presented here are also compared through the application to the real traffic network.